Baracuda broken

[Andi68]

THx kt,its easy for me, but that is all to do??

What means R8, Type=R_V_0.25

[kt315]

i wrote where to disconnect trace and connect to GND. it is not so hard to do.
also, set resistors values from George's schematic (look my BOM file).

[Qiaozhi]

Sorry, the schematic what i had posted was old.

I think this is the newest from kt315.

[ATTACH]42353[/ATTACH]

But this has nothing to do with the problem here in the thread.
I hope he can fix it soon.

My Baracuda Rev-B works fine.

If that's the correct schematic, then the pullup resistors are connected to the wrong power rail, the smoothing capacitors on the power supplies are incorrectly connected, and the voltage converter is an ICL7660 (which cannot handle the supply voltage). All these issues are described in the Geotech REV-A Build Document.

I've attached the Geotech Baracuda REV-A schematic so that you can see the differences. I note that kt315 has added some additional features.

[BKY1337]

Sorry, the schematic what i had posted was old.

I think this is the newest from kt315.

bara_sch.pdf

But this has nothing to do with the problem here in the thread.
I hope he can fix it soon.

My Baracuda Rev-B works fine.

[Qiaozhi]

Is the design of kt315 wrong?

I think that kt315 may have incorporated the changes in his version, but you will have to ask him.

[Andi68]

Is the design of kt315 wrong?

[Qiaozhi]

These problems were discussed over 2 years ago when several members were unable to build a Baracuda that was reliable. Sometimes the detector would work for a short time, and then fail, while others worked for a bit longer.

The problems were eventually resolved around March 2016, starting here (from post #432 onwards) ->

http://www.geotech1.com/forums/showthread.php?22964-Barracuda-Legend-Kit-Problems/page18

Impulse sent me his non-working Baracuda board for analysis, which eventually resulted in the Geotech Baracuda REV-A.

[BKY1337]

This here is Rev-A with schematic -> http://www.geotech1.com/forums/showt...roject-Details

The Board from Basti1983 is Rev-B without corrections (Georges Mod).

[Andi68]

So what is the schematic, with all the corrections?

[6666]

The pullup resistor mod will have a big effect on the depth.

[BKY1337]

I have a LT1054 mounted.

[Qiaozhi]

Yes, but this is not the problem. The Layout is working.

I had 25cm with a Euro and a 15cm Coil. Do you think i can double this depht with Georges Mod?

The pullup resistor mod will have a big effect on the depth. Also (if you don't make all the changes indicated in points 1, 2, 4 and 5) it will only be a matter of time before it stops working due to stress on the 7660A voltage converter.

[kt315]

to the depth George's mod does not have relation. George changed the connection of two resistors preventing burning out
of CMOS.

[BKY1337]

Yes, but this is not the problem. The Layout is working.

I had 25cm with a Euro and a 15cm Coil. Do you think i can double this depht with Georges Mod?

[Qiaozhi]

Hello, bad to hear that your Baracuda got damaged. Im the guy who sold you the Kit on ebay.
I can assure you that i only sent you good parts. I have built my Barracuda with the same parts, except the 7660 which was from Tayda-Electronics (12V max input).

I hope the guys here can help you with your problem.

What i would do is: Change all ICs. Then try it. If it wont work then change the transistors too.
But it should be possible to find the faulty part with measuring.

Its the Layout/schematic from kt315.

[ATTACH]42343[/ATTACH]

The schematic shown in your attachment contains the design errors described in points 1, 2, 4 and 5 in the Introduction of the Build Document.